1. Field of the Invention
This invention relates to a mold device for continuously producing a rectangular ingot for plate milling (which will be referred to as a slab hereafter) generally made of either aluminum or its alloys or copper or its alloys, and more particularly to a mold device for producing a slab with each different width by means of the same device by varying the width of each mold within a certain range.
2. Description of the Prior Art
Japanese Patent Publication No. 59-27672 discloses a width-variable mold device.
This conventionally available width-variable mold device has the following structure.
The mold for cooling and solidifying continuously a molten metal is equipped with a water cooled jacket at the outside, and furthermore, a pair of opposed and independent major side members with a water cooled jacket at the outside. The mold is formed in a plain and rectangular shape by means of a pair of opposed and independent minor side members placed between a pair of the above-mentioned major side members.
In each of the major side members, the interval between these major side members reaches its maximum at its center portion, and the mutually opposed inside surface is formed in a curved shape so that the interval between these major side members is becoming narrower as it gets to the sides of both end portions. In addition, each of the major side members is supported by putting a support plate installed to both ends of the upper portion of the major side member on an outer frame placed at the circumference of the mold so that each of the major side members may move toward the outer frame. Furthermore, each of the major side members is composed by inserting a pin fixed perpendicularly to the support plate into a slot formed along the moving direction of the major side member to the outer frame so that each of the major side members may move toward the direction varying the mutual interval within the length of the slot.
On the other hand, each of the minor side members is supported by putting a support plate installed at both ends of the upper portion in the minor side member on each of the major side members so that each of the minor side members may move toward the major side member. Furthermore, each of the minor side members is fixed to the major side members, respectively, by corresponding one of a plurality (four pieces) of bolt holes formed along the curved inner surfaces of the major side members toward the upper plate of each major side member to one bolt hole formed on the support plates at both ends of the minor side members in the vertical direction and then by screwing a bolt into the corresponding mutual bolt holes.
Therefore, by unscrewing the bolt screwed into the mutual bolt holes in the parts overlapped with the upper plate of the major side member and the support plates at both ends of the minor side members, moving mutually each of the minor side members so as to narrow the mutual interval between them, and corresponding the bolt hole located at the moving position in the plurality of bolt holes formed in the upper plate of the major side member to the bolt hole formed in the support plates at both ends of the upper portion of the minor side member in the vertical direction, a bolt is screwed into these bolt holes mutually. As a result, each of the major side members and the minor side members are fixed under the condition that the mutual interval between the minor side members becomes narrower and that between the major side members is also narrowed. On the other hand, by moving mutually the minor side members to widen the mutual intervals and corresponding the bolt hole in the upper plate of the major side member in the moving position to the bolt hole formed in the support plate of the minor side members in the vertical direction, a bolt is screwed into the hole mutually. As a result, the major side members and the minor side members are fixed under the condition that the mutual interval between the minor side members becomes wider and the area between the major side members is also made wider.
In the conventional width-variable mold device, as above-mentioned, the bolt hole in the support plate of the minor side members and one of a plurality of bolt holes formed in the upper plates of the major side members correspond to each other in the vertical direction, and the minor side members are fixed to the major side members by inserting the bolt into these holes. Therefore, the variation in the width of a mold (the mutually opposed interval between the minor side embers and that between the major side members) are restricted by the mutual interval between a plurality of bolt holes formed in the upper plates of the major side members. A weak point of the prior art is that the width of the mold could not be varied steplessly within the movable range of the minor side members.
In addition, when the width in the conventional width-variable mold device is varied, the bolt is loosened, and every time it is done, the conventional width-variable mold device must be moved by pushing and pulling the minor side members. Therefore, a problem created in that a time and labor are required for the operation of the minor side member in case the width of the mold is varied.